Shock absorber



Jan.3,1`92s. 1,655,206

J. A. STEVENS SHOCK ABSORBER Filed Sept. 9, 1926 2 Sheets-Sheet l A Jan. 3, 192-8.

J. A. STEVENS sHQcK ABSORBER Filed Sept. 9. 1926 2 Sheets-Sheet? Patented Jan. 3, 19278.

luurriazn STATES PATENT OFFICE..

'JOHN A. E EVENS, OF LOUELL, ASSACHUSETTS, A- SIGNOR TO PRODUCTS COMPANY. OF LQXYELL, MASSACHUSETTS, A OORFORATION OF DELAXVARE.

SHOCK ABSORBER.

.Application filed September This invention relates to shock absorbers and more particularly to devices absorbing shocks caused by quick relative movements ot two members. A specitic application ot the invention is a device intended tor use in connection with vehicles to absorb the shocks caused by the unevenness of the road, and while the invention is not limited to this use, it has many advantages which malte it peculiarly adapted thereto.

At the present time automobiles and other vehicles are provided with springs which absorb the lighter shocks, so that the occupants thereoic are only subjected to shocks ot the greatest intensity which also are softened and partially absorbed, so that a rolling or oscillatory motion is a'll that is normally transmitted to the occupants. However, when traveling at high speeds or over rough roads, and in any case when traveling long` distances, even this motion becomes disagreeable and is sometimes the cause of an illness, similar to seasiclness. lt is one of the objects ot this invention to counteract this dis- '.,Lable motion both by cushioning` the initial shock and by slowing` up or dampening` the rebound or recoil therefrom. This second action is especially important in the ase ot automobiles equipped with balloon tires which themselves act as shock absorbers,

but do not slow up the rebound, which results in the undulating or oscillating motion above referred to. rlhis invention is designed to overcome these diliiculties. A further object ot this invention is'to simplify the construction ot shock absorbers ot' this general type to malte them inexpensive tor use with cars ot' the lighter type. Other objects and advantages ot the invention will be apparent as the description proceeds and will be particularly pointed out in the appended claims.

Referring to the drawings in which is shown by way ot example two posf'ble enibodimeuts ot the invention,

Fig. 1 is a view in vertical section ot the I device, and

Fig. 2 is a similar view of the moditied form ot the device.

The numeral 1 designates the usual semielliptic leaf spring mounted on the axle ot a. vehicle and adapted to support the usual chassis or trame 2. In accordance with this invention a shock absorbing` device f designated as a whole by the numeral 3 is inserted between one end ot the leat springl 1 and the 9, 1926. Serial No. 134,404.

body or trame 2 which comprises a body portion L1 adapted enclose a pist-on rod 5 threaded on either end, A sleeve 6 is provided with a transverse shoulder or portion T, forming a piston, which is threaded to the piston rod 5, and is adapted to s'lide within a similarly shaped portion 8 ot the casingl, the piston thus being` guided in a predetermined straight path.

Surrom'iding the upper end ot the body portion i ot' the casing and suitably attached thereto, as tor example by screw threads 9, is a substantially spherical casing or cylinder l having; enclosed therein a hollow ilexible member or ball an outer casing of tal-)ric or other flexible material containing an inner casingl ot' rubber or other suitable material here shown merely as a single layer ot material 12 providing a compression chamber 11 therein. The inner casing or ball isadapted to be inflated through a suitable valve l-l attached to the casing` and extending` through the top ot the casing' 10, the valve 'la beingl ot the type commonly employed in connection with pneumatic casings. The piston rod extends through an opening 15 in an annular abutment 16 which may be integral with the body portion 4 and located substantially midway of the piston rod when it is in its normal position. The upper end of the piston rod 5 is provided with a suitable supporting head or pneun'iatic casing compressing' member 17 which may be sc ew-threaded thereto and which bears against the lower side of the casing 19 further to compress the air or other fluid within the compression chamber 11 on upward movement ot the piston.

A combined butter and check spring supportingl device is provided on the piston rod on one side ot the abutment 16 which may comprise a nut 18 threaded on the pistou rod and locked in any desire position by the check or loclt nut 19. Siuiported on nut 18 is a heavy spring 20 which normally terminates short of the abut-ment 16. This spring is elilective to provide a resilient. stop to the inward movement ot' the piston rod and is especially uselul in the application ot' the device to automobiles between the chassis and springs when a very heavy load is to be supported or when an extremely heavy shook is sustained by the vehicle; it is also uset'u'l in the event et failure of the pneumatic casing 12.

22 normally terminating short of the abut-V ment 16 similar to the spring 20. r1`he springs 20 and 22 may be retained against' nuts 18 and 21 respectively by means Yof flaring extensions 23 on each of the nuts engaging the end-most turn of their respective springs. Both spring 2O and 22 are normally not in operation, but are effective to cushion only extremely heavy shocks and rebounds respectively.

The casing may be provided above the abutment 16 with a suitable breather 241 l which may be constructed of an expanding nipple 25 threaded into a suitable aperture 26 in the side of body portion 4, said nipple being provided on the inside with a screen 27 and having threaded on its larger end a perforated cover 28 confining between it and f theV screen 27 any suitable packing material,

as for example, wool. This breather serves during the expansion and contraction of the casing'12 to exhaust or admit air from or to ythe chamber or space in the casing 10 surrounding the support 17, the air which is admitted to this space being filtered through the packing material in the breather 2li.

The portion 8 of the body portion 4 may be provided with a suitable groove 29 extending around it and communicating at one point with an opening 30 provided with interior threads for the insertion of a suitable oil or grease cup. rlhe piston head 7 may be provided with a drain opening 31 for excess oil or other liquid which may collect within the device.

The body portion 4c may be rigidly held t0 the chassis 2 in any suitable manner, as for example, by a bracket 32 which may be attached to the body l by bolts 33 and have therebetween a suitable dowel 811 for centering the bracket and body 4 respectively. The bracket 32 may be riveted or otherwise attached to the chassis 2 asshown at 35.

The body portion l is also preferably provided with a forwardly extending lug 36 having an aperture 37 therein for connection with a strut or bumper when the device is used at the front of an automobile.

The transverse portion 7 of the piston member 1 may be directly connected to the spring 1 as shown at 88 whereby the force exerted on the device by the spring 1 will be neither multiplied nor divided in its transmission to the piston.

Referring now more particularly to Fig. 2, the modilication herein shown is substantially identical with that shown in Fig. 1 with the exception that there is'provided between the transverse portion 7 of the piston 1 and the abutment 16 a spring 39 which acts in tandem with the pneumatic casing 12 in opposing inward movement of the piston; and there is provided between the supporting member or head 17 and the abutment 16 a spring 40, which is preferably somewhat lighter than the spring 39, tending at all times to oppose outward vmovementv of the piston relatively to the cylinder. This construction is vmore applicable for heavy closed cars or to other uses where a heavy load is to be sustained at all times or extremely heavy shocks are'to be absorbed. p It will be seen that I have invented a device which may take a very simple form and be inexpensive in construction, such as is applicable to light cars, and a modification thereof for heavier cars or analogous uses. l do not wish to be limited to the specific shape, size or construction of the embodiments of the device here shown and described, but merely by the scope of the appended claims. f Y

l claim: Y Y

1. A device for absorbing the shock caused by quick relativemovement of two members comprising a casing fixed to one ofV said members, a hollow flexible member Vwithin said casing adapted to be filled with a compr-essible fluid, a support within said casing adapted to engage said flexible member and to be moved to compress fluid therein,means for guiding the said support within the said casing, means for connecting the said support to the other of the said two members, spring means withinsaid casing adapted to check the movements of said support in both forward and return directions and means for maintaining the space within the casing surrounding the said support at substantially atmospheric pressure.

2. A device for .absorbing the shock caused by quick relative movement of two members comprising an outer casing iixed to one of said members, an inner casing of flexible material within said outer casing, said inner casing being adapted to contain a compressible Afluid, a support carried by the other of said members and adapted to engage said inner casing, a rod connected to said support, means for guiding the said rod within said casing, an inturned annular abutmentwithin said casing, a transverse shoulder connected to said rod, a spiral spring between said abutment and said shoulder surrounding the said rod and acting in tandem with said inner casing to oppose movement of the support in one direction, adjustable buffers on the said rod on either side of said abutment whereby to limit the stroke of said support, and a breather in said outer casing ladjacent to said abutment.`r Y

A device for absorbing the shock caused lll() by the quick relative movement of two members, con'iprising a easing` fixed to one ot said members, a piston rod connected to the other of said members and having' a sliding contact Within said casing, a liollov: flexible member Within said casing, said hollow member being' illed with a compressible iuid, an abutment on said casing adjacent to said piston rod, shoulders on said piston rod en either side of said abutment, a spring extendingfrom each ot said shoulders to said abutment, and an additional springlined to each ot said shoulders terminating` normally short of said abutnient, said adi ditional springs being effective only on an extremely heavy shock, one of said springs serving to cushion and absorb the initial shock and the other serving' to cushion and Vabsorb the recoil therefrom.

4. A device for absorbing the shock caused by quick relative movement ot tivo members, comprising a casing` fixed to one of said members, a rod connected to the other of said members, means having` a sliding;r Contact for guiding said rod Within said casing, an abutment on said casing adjacent to the said rod, shoulders on said rod on either side of said abutment7 a spring extending` from each of said shoulders to said abutment and an additional spring fixed to each of said shoulders and normally terminating` short of said abutment, said addi tional springs being` effective only on an eX- tremely heavy shock, one of .the springs serving' to cushion and absorb the initial shock and the other the recoil therefrom.

5. A. device for absorbing` the shocks caused by the quick relative movement ot two members comprising an outer casing adapted to be liXed to one of said members, a. collapsible inner casing filled with a compressible fluid, a support having` a rod connected thereto carried by the other ot' said members and adapted to oseillate in said outer casing, and collapse the inner casing and compress said Huid, a spring acting in tandem With said inner casing' to provide a. resilient resistance to movement of said sup port in one direction, and a second spring opposing,` movement of said support in the opposite direction.

Sig-ned by me at Lowell, Massachusetts, this 30th day of August, 1926.

JOHN A. STEVENS. 

